oj.uz

Submission #397532

# Submission time Handle Problem Language Result Execution time Memory
397532 2021-05-02T10:34:11 Z blue Swapping Cities (APIO20_swap) C++17
24 / 100
 2000 ms 347160 KB 
#include "swap.h"
#include <vector>
#include <algorithm>
using namespace std;

/*
Use Kruskal's algorithm.
For every node, compute sorted (by wt) list of edges that doubled its component's size.
Also compute the minimum edge wt that made it's component 'good'.

A component is good if it is not a single path.
*/

vector<int> W1;

vector<int> merges[100000]; //edge
vector<int> newcol[100000]; //color after merging
vector<int> goodEdge(100000, 2e9); //weight of smallest edge that made node's component good

void init(int N, int M, vector<int> U, vector<int> V, vector<int> W)
{
    W1 = W;

    int I[M];
    for(int i = 0; i < M; i++) I[i] = i;
    sort(I, I+M, [] (int x, int y)
    {
        return W1[x] < W1[y];
    });

    // for(int i: I) cerr << i << ' ';
    // cerr << '\n';

    vector<int> col(N);
    vector<int> col_list[N];
    vector<int> endpoints[N];

    for(int i = 0; i < N; i++)
    {
        col[i] = i;
        col_list[i].push_back(i);

        merges[i].push_back(0);
        newcol[i].push_back(i);

        for(int e = 0; e < 2; e++)
            endpoints[i].push_back(i);
    }

    for(int i = 0; i < M; i++)
    {
        int u = U[I[i]], v = V[I[i]], w = W[I[i]];
        // cerr << "cc:\n";
        // for(int j = 0; j < N; j++)
        // {
        //     for(int q: col_list[j]) cerr << q << ' ';
        //     cerr << '\n';
        // }
        // cerr << "wt = " << w << '\n';

        if(col[u] == col[v])
        {
            if(endpoints[ col[u] ].size() == 0) continue;
            for(int x: col_list[ col[u] ])
                goodEdge[x] = w;
            endpoints[ col[u] ].clear();
            continue;
        }

        if(col_list[u].size() < col_list[v].size())
            swap(u, v);


        bool flag = 1;
        if(goodEdge[u] == 2e9 && goodEdge[v] < 2e9)
        {
            endpoints[ col[u] ].clear();
            for(int x: col_list[col[u]])
                goodEdge[x] = w;
            flag = 0;
        }
        else if(goodEdge[u] < 2e9 && goodEdge[v] == 2e9)
        {
            endpoints[ col[v] ].clear();
            for(int x: col_list[col[v]])
                goodEdge[x] = w;
            flag = 0;
        }
        else if(goodEdge[u] < 2e9 && goodEdge[v] < 2e9)
            flag = 0;

        if(flag && (u == endpoints[col[u]][0] || u == endpoints[col[u]][1]) && (v == endpoints[col[v]][0] || v == endpoints[col[v]][1]))
        {
            if(u == endpoints[col[u]][1])
                swap(endpoints[col[u]][0], endpoints[col[u]][1]);

            if(v == endpoints[col[v]][1])
                swap(endpoints[col[v]][0], endpoints[col[v]][1]);

            endpoints[col[u]] = {endpoints[col[u]][1], endpoints[col[v]][1]};
        }
        else if(flag)
        {
            endpoints[ col[u] ].clear();
            for(int x: col_list[col[u]])
                goodEdge[x] = w;

            endpoints[ col[v] ].clear();
            for(int x: col_list[col[v]])
                goodEdge[x] = w;
        }

        int colV = col[v];
        for(int x: col_list[colV])
        {
            merges[x].push_back(w);
            newcol[x].push_back(col[u]);
            col_list[ col[u] ].push_back(x);
            col[x] = col[u];
        }
        col_list[colV].clear();
    }

    // for(int i = 0; i < N; i++)
    // {
    //     cerr << "i = " << i << '\n';
    //     cerr << goodEdge[i] << '\n';
    //     cerr << "merges: ";
    //     for(int m: merges[i]) cerr << m << ' ';
    //     cerr << '\n';
    //     cerr << "newcol; ";
    //     for(int n: newcol[i]) cerr << n << ' ';
    //     cerr << '\n';
    // }
}

int getMinimumFuelCapacity(int X, int Y)
{
    if(goodEdge[X] == 2e9) return -1;

    // cerr << "\n";
    // cerr << goodEdge[X] << '\n';
    // for(int i = 0; i < merges[X].size(); i++)
    // {
    //     cerr << merges[X][i] << ' ' << newcol[X][i] << '\n';
    // }
    // cerr << '\n';
    // cerr << goodEdge[Y] << '\n';
    // for(int i = 0; i < merges[Y].size(); i++)
    // {
    //     cerr << merges[Y][i] << ' ' << newcol[Y][i] << '\n';
    // }
    // cerr << '\n';


    int res = 2e9;

    for(int i = 0; i < merges[X].size(); i++)
        for(int j = 0; j < merges[Y].size(); j++)
            if(newcol[X][i] == newcol[Y][j])
                res = min(res, max(merges[X][i], merges[Y][j]));

    res = max(res, goodEdge[X]);

    return res;
}

Compilation message

swap.cpp: In function 'int getMinimumFuelCapacity(int, int)':
swap.cpp:158:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  158 |     for(int i = 0; i < merges[X].size(); i++)
      |                    ~~^~~~~~~~~~~~~~~~~~
swap.cpp:159:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  159 |         for(int j = 0; j < merges[Y].size(); j++)
      |                        ~~^~~~~~~~~~~~~~~~~~

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 4 ms 5268 KB Output is correct
4 Correct 4 ms 5452 KB Output is correct
5 Correct 4 ms 5580 KB Output is correct
6 Correct 4 ms 5580 KB Output is correct
7 Correct 5 ms 5580 KB Output is correct
8 Correct 10 ms 7500 KB Output is correct
9 Correct 335 ms 36116 KB Output is correct
10 Correct 434 ms 43064 KB Output is correct
11 Correct 433 ms 43060 KB Output is correct
12 Correct 455 ms 45380 KB Output is correct
13 Execution timed out 2112 ms 347160 KB Time limit exceeded

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 226 ms 27668 KB Output is correct
4 Correct 220 ms 28612 KB Output is correct
5 Correct 223 ms 28188 KB Output is correct
6 Correct 223 ms 28512 KB Output is correct
7 Correct 227 ms 28464 KB Output is correct
8 Correct 216 ms 27536 KB Output is correct
9 Correct 220 ms 28248 KB Output is correct
10 Correct 215 ms 27432 KB Output is correct

Subtask #3
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 4 ms 5268 KB Output is correct
4 Correct 4 ms 5452 KB Output is correct
5 Correct 4 ms 5580 KB Output is correct
6 Correct 4 ms 5580 KB Output is correct
7 Correct 5 ms 5580 KB Output is correct
8 Correct 10 ms 7500 KB Output is correct
9 Correct 3 ms 5324 KB Output is correct
10 Correct 6 ms 6220 KB Output is correct
11 Correct 5 ms 5624 KB Output is correct
12 Correct 5 ms 5708 KB Output is correct
13 Correct 5 ms 5708 KB Output is correct
14 Correct 6 ms 5836 KB Output is correct
15 Correct 5 ms 5708 KB Output is correct
16 Correct 5 ms 5580 KB Output is correct
17 Correct 10 ms 7628 KB Output is correct
18 Correct 6 ms 6032 KB Output is correct
19 Correct 8 ms 7116 KB Output is correct
20 Correct 5 ms 5712 KB Output is correct
21 Correct 10 ms 7756 KB Output is correct
22 Correct 5 ms 5708 KB Output is correct
23 Correct 7 ms 6352 KB Output is correct
24 Correct 6 ms 5708 KB Output is correct
25 Correct 8 ms 6604 KB Output is correct
26 Correct 5 ms 5708 KB Output is correct
27 Correct 12 ms 8144 KB Output is correct
28 Correct 14 ms 9164 KB Output is correct

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 3 ms 5324 KB Output is correct
4 Correct 4 ms 5268 KB Output is correct
5 Correct 4 ms 5452 KB Output is correct
6 Correct 4 ms 5580 KB Output is correct
7 Correct 4 ms 5580 KB Output is correct
8 Correct 5 ms 5580 KB Output is correct
9 Correct 10 ms 7500 KB Output is correct
10 Correct 335 ms 36116 KB Output is correct
11 Correct 434 ms 43064 KB Output is correct
12 Correct 433 ms 43060 KB Output is correct
13 Correct 455 ms 45380 KB Output is correct
14 Execution timed out 2112 ms 347160 KB Time limit exceeded

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 4 ms 5268 KB Output is correct
4 Correct 4 ms 5452 KB Output is correct
5 Correct 4 ms 5580 KB Output is correct
6 Correct 4 ms 5580 KB Output is correct
7 Correct 5 ms 5580 KB Output is correct
8 Correct 10 ms 7500 KB Output is correct
9 Correct 335 ms 36116 KB Output is correct
10 Correct 434 ms 43064 KB Output is correct
11 Correct 433 ms 43060 KB Output is correct
12 Correct 455 ms 45380 KB Output is correct
13 Execution timed out 2112 ms 347160 KB Time limit exceeded

Subtask #6
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 3 ms 5324 KB Output is correct
4 Correct 4 ms 5268 KB Output is correct
5 Correct 4 ms 5452 KB Output is correct
6 Correct 4 ms 5580 KB Output is correct
7 Correct 4 ms 5580 KB Output is correct
8 Correct 5 ms 5580 KB Output is correct
9 Correct 10 ms 7500 KB Output is correct
10 Correct 335 ms 36116 KB Output is correct
11 Correct 434 ms 43064 KB Output is correct
12 Correct 433 ms 43060 KB Output is correct
13 Correct 455 ms 45380 KB Output is correct
14 Execution timed out 2112 ms 347160 KB Time limit exceeded